The service, jointly run with marketing list vendor Database America, just launched two weeks ago and allowed Net searchers to put an instant finger on 175 million people, all culled from commercial mailing lists.
However, many of the published addresses and phone numbers were unlisted, and their availability drew the ire of privacy advocates and citizens, like police officers and judges, whose safety depends upon privacy.
After considering complaints, Yahoo yesterday decided to block any record that didn't include a publicly listed phone number. The records have now been winnowed down to 90 million.
The problem won't necessarily disappear, privacy experts said. "People don't know that when they get an unlisted number, the phone company will still put it in a database that they sell," said Stanton McCandlish, online activist at the Electronic Freedom Foundation.
Personal information on commercial mailing lists can also originate from credit card purchases, magazine subscriptions, and in some states, driver's license records.